Expansible pipe fitting



July 26, 1949. G. w. SMITH EXPANS IBLE PIPE FITTING 2 Sheets-Sheet Filed July 25, 1947 INVENTOR. /& ,M BY W MZM Patenlz'ed July 26, 1949 UNITED] STATES PATENT] OFFICE EXPANSIBLE PIPEFIVTTING George w. Smith, Union, N. J. Q Application July 25, 1947, Serial o. 763,553

, The present invention relatesto, air ducts and fittings such as are employed in the construe-,- tion of air conditioning and heating systems and is concerned morefparticularly with improvementsin the individual parts and component elements. The'invention has for a primary objective aj simplified and improved construction of various fittings whereby and wherewith the fittin is readily adaptable to meet a particular condition encountered in any given installation. The invention further undertakes to render available a new design of fitting embodying the on-the-job fabricating characteristics above mentioned and which also embodies features operative, on the installation of the fitting, to effect a stream-lining of air flow through the various parts'of the system. v

Still afurther aim'of the invention is to render available a system of fitting fabrication that may befutilized inthe construction of any of several distinct types of fittings, for example, as a 45 elbow, or a 90 elbow, a branch take off, a reducer or an enlarger, in either the trunk or the branch lines of the system. a a i Heretofore the customary practice has been to manufacture the various fittings as complete units, each innumerous sizes, and the journeymantinsmith, was obliged to install the fittings in the size and shape that those particular fittings were furnished by the manufacturer and jobber.

In consequence, the tinsmith had to carry to the job a wideassortment of sizes andshapes of each kind fof fitting and expect that among the range of sizes, one would be found to meet each ofthe particular conditions encountered at the point of installation. Attempts to modify or change the size of a completelyprefabricatedfitting was not very successfully-understakenand often impossible because of the various seams, beading and lock joints, etc., that must be cut into in order to improvise. Moreover, the prefabricated fittings in common use have heretofore been constructed as a complete unit, and it became necessary for themanufacturer to produce, and the dealer to carry in stock a large inventoryof the many difference types,as well as sizes, of fittings. Also, the Prefabricated fittings, did not lend themselves adapted for nesting, and many are damaged in transit notwithstanding careful packaging and handling. i o

In accordance with this invention, the various fittings may be constructed or prefabricated in a manner affording a wide range of adjustment in 4 Claims. (01. 285-205) Moreover each fitting, embodying the principles of this invention, is inherently capable and adapted for alteration as to size in two directions so that a given fitting may be partially fabricated by the manufacturer and fabrication completed on-the-job to suit the condition needed. A1 though it is the customary practice to lay out on paper the sizes and courses of the various trunks, stacks and ducts together with their various fittings and branch connections, conditions are frequently encountered on installing that require a re-routing, or shifting, or change in location shape or size of a fitting that had not beenanticipated. Considerable delay and extra work is necessary therefore in obtaining the proper fitting or improvising a poor substitute. On the other hand, fittings constructed inaccordance with this invention, embodying as they do,substantial universal adjustability in size, and an equal degree of flexibility as to shape, together with adjustability-as to the location of the point i of connection or union of the different parts of the system, the various problems encountered at the time of making an installation, are quickly overcome. i i

In carrying forward the aims of this invention, it is now proposedto fabricate the various units in a plurality of sections. In most cases the number of sections per unit will total 4, each being characterized byat least two extensions- (perimetrallydisposed) one of which is fixed as to length and provided along its extreme edge preferably with the female portion of a joint or seam, and the other of which is a plane sheet whose extreme edge constitutes the male part of a seam or joint. In the case of corner sections, for example, all are similarly formed and interfit to form a parallelogram of a certain maximum size. Should it be desired to decrease the sectional area of the parallelogram, it is necessary only to trim down the male extension of comple-v As to.certain fittings, such, as the plenum, chamher, two or more of the sides that form corner sections may be given an outward flare, which on assembling, forms a throat for an angle bend as at the juncture of a trunk line with the plenum chamber. To facilitate the trimming operation, the male extension of each section preferably is ruled or scored with numbered parallel lines which serveas guides to indicate how much to trim off to produce an assembled fitting of a preselected or a standard size.

The invention is carried out in a similar manher in respectto elbows, offsets, and take off fittings for it is proposed to construct each of the fittings of a; plurality of sections, with male and female seam portions, preferably ruled as, above indicated. ,By trimming the male portion of se- 3 lected sections the required amount and then assembling and securing the seams, as with a conventional lock, the sectional area of any given fitting maygbe: constructed on-th'e iobeto-s;uit.,re--- quirementseontlie conditions encountered...

Additionally, this invention proposes further improvements in a sectionalized fitting wherebit".

a take-off connection at any desired point. along,

the trunk or duct may be made. "Eferetofore take-offs had to be made at the extrem'eafendioii.

a fabricated section but with the aid oi this invention one or more parts of the improvedfitting may be shifted longitudinally of complementin portions of the trunk or: another fitting to suit special, requirementsandl the seams then locked together. The uncovered}.portion.offtheassehibly,. iebl'smlied, ofiby, anextendi'ngit'ail piece on the takeeofilsection, or: by a separate 'piece, or by another takei-off,-as may. be expedientin. a given. installation.

Other obj cats, and. advantages. will belin, part. indicated; in the following descriptioniand in part. rendered? apparent .therefro'mtin connection with the annexed-t drawings,

Toenable others: skilled in the art sorfullyi 120,. apprehend; the underlying? features; hereof that;

22 of Fig. 1, of the two-way adjustableioffesetl,

ttings-i.

Eigi 3.is a detail sectionaiiviewiofrazlook seam: EigSSIA iandafizara sideand-ztop views respectively;

ft: a2. plenum chamber. constructeds for; adjustemen n 1eng-tmwidth, and heighhiandiwith and; withoutiaefiaringefon trunkzconnectionsx Fligse Grands-.7 are detail viewsiofi"optionalicornerzr sectionsaioi therfittingi. a y

- Eig'c 8:-lis:-:a1' line: zdi'agra-m iof aapreferredimethod' z enjoining omponentzelementssof theifittings 9 saxplaniivievttofi'one side of; an elbow fitting;

Fig-alox-is an end viewithereofi Fig. 1 i3 is aipartially asse'mbled View offi 'an adejusta-ble=.take-ofi fitting: together: with amelbowa snake-as illustratediin lltig'ss Qs'zand 1-0.

Referring:moreiparticularlyto the representa tive syst'em illustrated" -in- Fi'gcl, W designatesa warm airiiurnace embodying the-conventional I blowetthat forcesheated air into'-auplenumzcham'- ber P-i-thenoe -int'o'a main trunk line T an'd bra-now joint.

awai

4. ing provided along its marginal edges with male and female joint portions [5 and 16. Where, as here illustrated the sections a, a", etc., are also comer sections; iiz is preferred to makeithe sides I1 and l8i-unequal in length and. the equip the shorter side I8 with the. female portion of the It will be understood that four of such sections are. designed to interfit with one another to 'fbrma rectangular figure. In installations where thezfiirnace opening is smaller than the area inscribed by the four interfittlng sections,

the male extensicn of opposed pairs of sections fiare liLgonone or. both. of; itseiitensions, as .de-. sirecL- Theeupper. marginaLed'gesof-Zthe sections.

only partiall-y fiattenedi. It..,will beiund'erstoodi however thatiallSuohsseamsare fiattened'itightly oncompltion.oi.:amassemblmo insure iiirmtunion... of thepartsaswelliasstoeprodncesmooth surfaoes;

inside..and.-outsideloi;theaducts. Fig,-. 4Lillustrates,

a sectionalized plenum chambenofiasiz ethatfitm a. whole; trunk. section whereas in: Eigul. the plenum.- chamber; is; vion thee purpose: of; illustrae V ti'on.; shown as;being shonterathanaztrunksection;

The size ;-of' thee plenum mayg im accordance-with; thisinvention, bzafittedeto any size trunkemerelyr. by; cutting into the'underlductile.thereof; inserting;I and flattening down the extensionflanges'cf' of: the ,respectivejsectionsr bi,- etQu The-end; of

astrunleilineris closediiinaoonventional manner. by?- a side-; wallipiecee c that iss-lockediswmedebout;

itsamargins-tzithezwalls piitheetrunk, 1118117011.:

'ofithei plenum: chamber; is; with: thiscmethodi of= construction, theiumier:wall ot astnunkgwhereby;

lines B} B, B leading to the variousepartsofia building;

' f rringfirst: to: the plenum'a chamber: parsed also see me), this fitting-functionssomewhati as azjunction box';whereat one-or more tnun-lelines are initially connectedi The lengtli and width of theplenumachamber varieswitline'arly; everymake of furnace, and' -its lie-i'ght' varies in nearly every installation; In accordance=-with-tlfiinvention; it is* now proposed to fabricate -suclia unit in two't'iers a and b; and each tier" being-=- airzfrnmithe plemumchambeniintosthe nlsline: ort'lines-iwhenez tiieyz-join' zthee chamber-s... 'Ilies outs ward flaring of;thecwailssbfzforms:zaithroatiopene k inggx 3.85? in 21am elbow ianidiavoidseextremei eddyingg, andkde'adiaiiiixpoeketsiat-thatijnnctioripoint:

In a si-tnilamway, elbows and'i bends: (E1 inc. Figs;- hand-1 D araconstruetedi: .9: illustratess one sid of elbow; in which"' tlie sheet. eihaissits Outfi poiltifini: curved; and-3. fasten iva' converitional wayg toasfiangespiecez e-'-. Thecenter of a; cu-rvature' lies wel-l inside: the -margihs of the'slieet at the poii' i indicated by -a-small oiicle -19 fireflies-9. 'lhe-throati portion Ofzitli' slfieet is out in t form of awsquare; the diagonai of whichilies on a hile-mtrsectil ig the center oi curvature of 'tiie h'eei portion and which line also bisects the angle formed :by the extremeouter*edges* lfi and 2% of thESHG'Eilf A' slieet-so constructed is: it will be seen; adaptable its eitherrigl it or lei-t hand elbbws; zone of the sheet i's -prefrably ruled: two -ways;- by= a seriesof: equally spaced pa-raill lines e"-'" which arenumbered-in sequence irom the centiali port-iontowa-rd tiietliroat pertiom The fi-rst lifre will'fo'r' examplesbe numbered 'lf thenext linef-8j thenext lined)? and-sown the'nuinber 'l -'iri-clicat ingthat' tlie distanc'e' -betweewthatline= and"theiouter edge is seven inches. The'last"="line"NO'.'

-- speei'allyw constnuctedi The throat V 24, indicates that -theelbow maybe 24 inches in width. These lines are provided toserve as a ;guide;to the tinsmith to enable him. quickly to trim the sheet to the required size of elbow needed. The throat piece ,e3, shown detached in" Fig. 9; is thereafter inserted and completes the elbow. The throat piece is flanged at its side, and fashioned with a snap lock seam portionZZ and 23 that interlock with complemental indentations made in the sheet after it has been trimmed to size. Also the throat piece e3 is formed with a curved throat wall e4. whereby to improve the air flow around the corner. Fig.9

illustrates in dotted lines, a typical location of: the throat piece in constructing an elbow of a.

predetermined size smaller than the original sheet. The region of thesheet e adjacent one of the outer edges, e. g., 2| is also ruled with a series of parallel lines that extend to the outer seamed edge at. Where the lines intersect the edge e6, the seam atthat point is previously fitting is disclosed in connection with a 90 elbow,

the invention is also applicable to 45 elbows, as will be evident. It will also be understood that the opposite side wall of the elbow to be fabricated is constructedwith perpendicular flanges as above explained, andthe flanges of the two sheets secured together by throat and heel spacer sheets el and e8 respectively. The connecting sheets are connected to the flanges ed and e, by conventional interlocking seams and may, of course, be trimmed to the width that is desired in constructing a bend of a certain cross-sectional area or capacity.

Fig. 11 illustrates the invention as applied to a branch take-off fitting F positioned on an elbowG. i

l The sides I of the take-off fitting F are ruled with. parallel lines I that extend lengthwise the fittingand which serve as a ready guide and capacity indicator. In duct work of this general character, a system of sizes has been developed and tables worked out whereby the tinsmith may determine how much a trunk line, or other conduit, should be reduced in width to compensate for a take-off of a given size. To reduce frictional losses it is preferable, where possible, to

make the reduction (or enlargement as the case may be) in one direction only, for example in the width of the duct. The lines I on the sides otthe fitting F in Fig. 11, afford convenient-touse indicators of the several capacities of a fitting so constructed. In assembling the fitting, the tinsmith trims ofi the excess stock and joins the cut edge to an adjacent section, illustrated at G, by means of a slip joint member 26 or other suitable seam making member. If desired, the cut edge on the fitting F may lap the surface of the adjacent fitting and secured as by riveting.

The open end i of the take-off fitting F, is usually adapted for connection with an extending duct line (e. g. B in Fig. I) and where the capacity or width of the branch duct, is predetermined, the fitting F mayhave its open end j altered. to suit. As indicated in Fig. 11, the

depth and heel portion To close in the width of the open end of the fitting, the fitting is taken apart and the male extension portion of the parts trimmed oil the amount required to produce an elbow take-off of a particular size. The sections are then as- In the installing of fittings embodying the ad justability features of this invention, the work-H men need cut across unseamed plane sheets only Where cuts to be made intersect a corner seam,

the corner seams are previously notched as illustrated at e and f in Figs. 9 and 11. Both sides of the fitting are trimmed to the notches in the corner scam, the perpendicular wall (e. g, e in Fig. 10) is bent away from the rim and cut across.

from one side to the other. In general, however,

the workmen will out along a ruled line on the fitting of the next largerindicated size, and the extra inch (assuming 1 inch spacing of the lines) provides stock for the joint or seam.

Where it is found desirable or expedient, to

make a take-01f in the middle of a standard? length duct section, or nearer one end than the other, each adjustable take-off is constructed,

with an extending tail-piece, indicated at f in Fig. llwhich may be easily trimmed down to the length required to bring the open end of the takeofi" at the desired point lengthwise the trunk. Fig. 1 illustrates an elbow adjacent the plenum end of, a trunk section, a take-oif F intermediate the ends of a trunk section, and a take-01f FF positioned at the far end of a trunk section. Where, desirable, two take-offs may be located in succession in the one trunk section and the trunk reduced proportionately. When a take-off is positioned below the transverse seam of a trunk section, the remaining open side of the trunk is covered by a piece J (Fig. 1) which overlays the folded back edge I or g in Fig. 11, and locked seamed along its edges with the side walls of the trunk.

In the drawings, referring more particularly to Fig. 1, the interfitting and locking seams are represented simply bydouble lines at the points where they occur, and inasmuch as this invention does not concern the seam per se but instead its location and disposition of the male and female portions on the respective sectionalized fittings, a I

more 'detailed illustration of the seam is deemed unnecessary. Any of the standard or conventional forms of'locking seam may, of course, be

used in practicing the invention. A preferred style of locking seamis illustrated in Fig. 3 and is known as the S Slip lock. That type of lock joint comprises the crescent shaped indentations 24 spaced near and along the edge of the male extension of a sheet, and an inwardly tucked edge 25 of a doubly folded edge 22 of the female part of an adjacent section. As the portions are assembled, the indentations 24 move past and lockbehind the inwardly folded edge 25 and the two sections of the fittings are united substantially as 'a contiguous member. Where two male extensions are to be joined a Z type clip, illustrated at 26 in Fig. 11 may be employed.

Figs. 1 and 2 illustratethe invention of an fi-oi the fitting is a piece separate from the throat and tail portion f but is her mally locked thereto by. a locking seam joint it 1 mm eintport onalong c t adiustdple fitting apt-Heatean cii-set-nttnig H; Essentiany this fitting is ucted gt indijl ual earner section's n to sectiens; or lenum chain a new fitting n;

erP pfi s'et; however, as its upper and lower one of the "fit g ant ends anprexima v central of the side wall of the other and offset/ end 01 the nan-re, nceorai naly, the maleextension of tltecornersec o" tn what eacaena (o'r lawer') walla n-th W0 sections areas 1 and the se'afiilocked, th' ifse'ijwill be depth teacnena; 'Va'ri risi width of e enset are accomp shed Winter ocking a :siacr Sheet it of the r ci'iiir'ed' Width the .li-tt e amenity is had curving the p'lansbf the sheet ta fit the Vatnr'e' of the flanged" portion lof'the'cornersecti as; e

From the foregoing it will be perceived that it fisnow'i'possibie to f :1 such ainannerfthatthe-workmen may tlt andi la inbl-fe the sections in the particular sizie req ed f "the 'in'stalilationyand to effect the assembling a minimum of time and eil'ort.

Moreover, fittingssof made offer the least r'esist :anbetoair new, lie-cause tithe-large throat 0156f).-

jna made possible by sec'ti oiializ'in'g' the different gs; Additionally, fittings constructed in accordan'ce with thisinvent'i-on are neat in appeariance, sturdilt seamed, and when in knocked down :and nested condition, occupy considerably less a space than the conventional-fully prefabricated Withoiit further analysis; the foregoing will so L'fdlly' reveal the gist of this invention that others: lean-b applying current knowledge, readil 'aeant :it' for variou utilizations by retaining one or" or the features that, from the t of the prior art, fairly constitute essentiaic arjf' acteristics of either the generic or specific aspe ofthisintentlonand; therefore, s'uchadap-tati' should be, awar intended tebe; comprehended within the meaning" range of equiva ency or the followingfolairns;

new a'ndde'sire' to secure the-re owing 'conib nawens and elements, or equivalents trier-ear; 153* Letters Patent er theUnitedStates': e

1". A'partially prefabricated air ductlfi t'ting r'o'r' use ir'i'l ieating' and v'ritilat'ing systems com-prised of atile'astfour sections adapted on being as sembled to forma tour sided air duct; 'eachof said seotions bei-ngcomposed of sheet-like ma terial bent'medial-ly of its side edges toform' a corner piece; and each" section havinga f'emal'e joint- .portion along one side edge'and a' coinple menting male joint porti-c'ir-i along its other side ed e; and each "of said sec 0 e v ts en dgesanif le porticn longth'end edg'ecpposltasaid ma; join-t portions of each seetibnlieing com: prisd ofj'the at planefofthesheet armed d' for conveiii zit whereby a dim ofapr selectedlehgt'fi', Width andueptnrfiasfte coinicate air ducts and fittings Having thhsrevealed tl'iis invention, 1 claim" as err-along aiine from tl-ie upper cater edgswhereby t'o'for'rn a U-shaped strutp'i'eted assembled on the jobto salt area requirements.

A partially prefabricated elbow remnant" uSe in a heating or Ventilating syster'rt-com ingtwo sheetmembers having corre'spondinglj" carved eag he aids or urvaturelyirr within-- the margins of the Sheets,- and a wall i'n'elh inter locled with said sheets along the ci'u any ros's-seti0nal plane of the elb W, "'te throat-piece for the elbow fitting 00 am a curved member proifided with uptifl ed fla es alongeach side adapted to interlock w lit the inner edge portions of said first-merino fd= rneii ibels -and" to fori ntherewith a curved to the-elbow, the saidinner ermanent said first mentioned sheet members having flat plane-edge portions adapted to be trimmed back as needed wherebythe fabrication of an elbow fitting of a} presel'e'cted sectional area at its entrance ginal edges, 'said last mentioned wall constitutinig part at least of the heel portion of an elbow fit ting, one of said'hee'l'an'd throat assemblies haw ing a female seam po'r'ti'on along its edges and the other of said' assemblies having a male seam portion; along its edges adapted for interiitting' withthe se-arnportions of the said-other assembly toform a four sided elbow conduit; saidmale seam-portions-of thafitting being composed ofthe flat plane edge portions of the members and capable of being trimmed back as needed whereby the fabrication; ofan elbow fitting of a ipredtermined sectional area as to "one of openings may be completed on the site of use;

4; A partially prefabricated air duct for use in a heatingor ventilating system comprising at least fou-r sheet-li-ke blanks; each of said blanks being bent medially ofits side edges as tdforin a cornersection' capable-of compact nesting others, and each of saidblanks being initially formed with a female sea-m portion along its-left side edge and amale'seam portionalong' the rightside edge designed ,for interfittin with comple n e'ntary seam portions of another adjacent sec t on on assembling the four blanks tog-ether to form a four-sidedconduit, the said male seam portion of each blank consisting of the plane un confignred edge portion of the'sheet and adaptedfor easy trimming on location to a narrower widthwhereby fabrication of a duct of a selectedsize as to depth and width may be completedonthesit of Ilse.

enema w. 7 RE ERENCES cram Thefollqwing references are of'recora in tlie' UNITED STATES PAIENT" Name 7 I 7 D i at Dec; s raw Jones et *al;

Somers Mar. 10, 1942 iii at 2,275,572

a Jan; 751 1941 

